JPS5821834B2 - Manufacturing method for wiring boards - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a wiring board that requires plugging.

In recent years, wiring boards (hereinafter referred to as multi-wire wiring boards (Hitachi Chemical @) product name) that use insulated wires (hereinafter referred to as wires) for the necessary wiring patterns.

) has begun to be used in data processing equipment, communication equipment, electronic application equipment, etc. as a high-density wiring board suitable for small-scale production of a wide variety of products.

Multi-wire wiring boards are made by forming a circuit pattern on one or both sides of an insulating substrate such as a thermosetting resin laminate using the usual etched foil method, and then running wires over the circuit pattern (excluding the plug part). When wiring is bonded at the same time, an insulated wire coated with a heat-resistant resin such as a polyimide resin ( Wire), laminated and glue prepreg, etc. to fix the wire, and at the end of the wire, make a through hole that crosses the wire, exposing the cut end of the wire on the peripheral wall of the through hole, and cut the wire on the inner wall of the through hole. It is manufactured by forming an electroless metal layer connected to the end.

When electrically plating gold or other metal (plug plating) on the circuit pattern connectors of this multi-wire wiring board, conventionally it was done after forming the circuit pattern on one or both sides of the insulating substrate by the usual etched foil method. was.

For this reason, when plating the connectors, the circuit pattern made of the copper foil layer is exposed, and in order to protect the circuit pattern from the connector plating solution, a plating protective mask is applied to the part of the circuit pattern other than the connectors, and from the border of the protective mask. To prevent infiltration of plating solution, thermocompression bonding is required at the border of the protective mask.

That is, as shown in FIG. 1, a circuit pattern 3 including a plug 2 is formed on one or both sides of an insulating substrate 1.a) A plating protection mask 4 is applied to the portion of one circuit pattern excluding the plug.b) ), the boundary part 5 of the protective mask is thermocompression bonded and the plug is attached (C).

This complicates the manufacturing process, and improvements have been desired.

In this multi-wire wiring board, after a circuit pattern is formed on a copper foil layer, an adhesive layer is laminated, bonded, applied, or thermocompressed on the circuit pattern (excluding the plug), and then wires are laid and the wires are fixed. In order to do this, the plug plating is performed after the prepregs are laminated and bonded, thereby omitting the formation of a plating protective mask during plug plating and the thermocompression bonding of the boundary portion of the protective mask.

The present invention will be explained with reference to FIG.

First, a circuit pattern 3 including a plug 2 is formed on one or both sides of an insulating substrate 1 (a).

After laminating, applying, or thermocompression bonding the adhesive layer 6 on the circuit pattern except for the plug, wire the wire 7b),
In order to fix the wires, prepregs are laminated and bonded to form a surface coating layer 8, and then (C) plugging is performed.

This makes it possible to omit the work of applying a surface protection mask and thermocompression bonding to the boundary surface, simplifying the process and reducing the amount of auxiliary materials.

The present invention is not only for the multi-wire wiring board described above, but also for the circuit pattern excluding the plugs.
A similar effect is achieved when applied to wiring boards on which a surface coating layer of a thermosetting resin layer is formed to prevent mechanical damage.

[Brief explanation of drawings]

The drawings are plan views illustrating the manufacturing process of the wiring board, and FIG. 1 shows the conventional case, and FIG. 2 shows the case of the present invention. Explanation of symbols, 1... Insulating board, 2... Connection, 3... Circuit pattern, 4... Plating protection mask, 5...・Plating protection mask boundary, 6...Adhesive layer, 7...Wire, 8...
...Surface coating layer.

Claims (1)

[Claims] 1. A method for manufacturing a wiring board comprising the following steps. a. Form a circuit pattern including plugs on an insulating substrate. b. Forming an adhesive layer on the circuit pattern excluding the plugs. Wire an insulated wire on the C6 adhesive layer. d. Forming a surface coating layer on the wiring wire. e. Fit the connector. f. Drill a through hole across the wire and form an electroless plating layer on the inner wall of the through hole.